The vast majority were found at the Yinxu site. They record pyromantic divinations of the last nine kings of the Shang dynasty, beginning with Wu Ding, whose accession is dated by different scholars at 1250 BCE or 1200 BCE. After the Shang were overthrown by the Zhou dynasty in c.1046 BCE, divining with milfoil became more common and it is also the oldest known member and ancestor of the Chinese family of scripts, preceding the bronzeware script. The term oracle bone was first coined by the American missionary Frank H. Chalfant in his 1906 book Early Chinese Writing, because turtle shells as well as bones were used, the oracle bone script is also sometimes called shell and bone script. As the majority of oracle bones bearing writing date to the late Shang dynasty and it is certain that Shang-lineage writing underwent a period of development before the Anyang oracle bone script, because of its mature nature. However, no significant quantity of clearly identifiable writing from before or during the early to middle Shang cultural period has been discovered, the oracle bone script of the late Shang appears pictographic, as does its contemporary, the Shang writing on bronzes. The earliest oracle bone script appears even more so than examples from late in the period, additionally, the writing of characters in vertical columns, from top to bottom, is for the most part carried over from the bamboo books to oracle bone inscriptions. The vertical columns of text in Chinese writing are traditionally ordered from right to left and this level of maturity clearly implies an earlier period of development of at least several hundred years. Compare, for instance, the third and fourth graphs in the row below, without careful research to compare these to later forms, one would probably not know that these represented 豕 shĭ swine and 犬 quǎn dog respectively. By the late Shang oracle bone script, the graphs had already evolved into a variety of mostly non-pictographic functions, phonetic loan graphs, semantic-phonetic compounds, and associative compounds were already common. Although it was a fully functional writing system, the oracle bone script was not fully standardized, a graph when inverted horizontally generally refers to the same word, and additional components are sometimes present without changing the meaning. These irregularities persisted until the standardization of the script in the Qin dynasty. Of the thousands of characters found from all the fragments so far. One reason for this is that components of certain oracle bone script characters may differ in later script forms, such differences may be accounted for by character simplification and/or by later generations misunderstanding the original graph, which had evolved beyond recognition. Another reason is that some characters exist only in oracle bone script, in such cases, context - when available - may be used to determine the possible meaning of the character. One good example is shown in the fragment below, labeled oracle bone script for Spring, the top left character in this image has no known modern Chinese counterpart. One of the better known characters however is shown directly beneath it looking like an isosceles triangle with a line cutting through the upper portion. This is the oracle bone script character for 王 wáng, the numbers of oracle bones with inscriptions contemporaneous with the end of Shang and the beginning of Zhou is relatively few in number compared with the entire corpus of Shang inscriptions
Image: Shang dynasty inscribed scapula
Wang Yirong, Chinese politician and scholar, was the first to recognize the oracle bone inscriptions as ancient writing.
Image: CMOC Treasures of Ancient China exhibit oracle bone inscription